1. Field of the Invention
The present invention relates to disk drives. More particularly, the present invention relates to vibration isolating disk drive receiving stations and chassis used in the manufacture and/or testing of disk drives.
2. Description of the Prior Art
FIG. 1 shows the principal components of a magnetic disk drive 100 with which embodiments of the present invention may be practiced. The disk drive 100 comprises a head disk assembly (HDA) 144 and a printed circuit board assembly (PCBA) 141. The elements shown and described in FIG. 1 may be at least partially incorporated within the PCBA 141. The HDA 144 includes a base 161 and a cover 171 attached to the base 161 that collectively house one or more disks 200 (only one disk 102 is shown in FIG. 1), a spindle motor 113 attached to the base 161 for rotating the disk 102, a head stack assembly (HSA) 150, and a pivot bearing cartridge 184 that rotatably supports the HSA 150 on the base 161. The spindle motor 113 rotates the disk 102 at a constant angular velocity, subject to the above-described variations. The HSA 150 comprises a swing-type or rotary actuator assembly 152, at least one head gimbal assembly that includes the suspension assembly 154, a flex circuit cable assembly 180 and a flex bracket 159. The rotary actuator assembly 152 includes a body portion 145, at least one actuator arm cantilevered from the body portion 145, and a coil assembly including a coil 156 cantilevered from the body portion 145 in an opposite direction from the actuator arm(s). A bobbin 158 may be attached to the inner periphery of the coil assembly to stiffen the coil assembly. The actuator arm(s) support respective suspension assembly(ies) that, in turn, support the head that includes the read/write transducer(s) for reading and writing to the disk 102. The HSA 150 is pivotally secured to the base 161 via the pivot-bearing cartridge 184 so that the read/write transducer(s) at the distal end of the suspension assembly(ies) may be moved over the recording surface(s) of the disk(s) 200. The pivot-bearing cartridge 184 enables the HSA 150 to pivot about its pivot axis. The “rotary” or “swing-type” actuator assembly rotates on the pivot bearing cartridge 184 between limited positions, and the coil assembly that extends from one side of the body portion 145 interacts with one or more permanent magnets 190 mounted to back irons 170, 172 to form a voice coil motor (VCM). When a driving voltage is applied to the VCM, torque is developed that causes the HSA 150 to pivot about the actuator pivot axis and causes the read/write transducer(s) to sweep radially over the disk 102.
Thereafter, the PCBA 141 may be mated to the HDA 144 and a variety of tests and procedures may be carried out to configure, validate and test the proper operation of the disk drive. Such testing may be carried out in a “single plug tester”, which is a test platform that includes a chassis that includes a bank of slots or bays into which the disk drives may be loaded and unloaded. A sequential series of tests and operations are then carried out on the loaded disk drives. Conventionally, the drives remain in the same bay during the administration of the entire sequence of configurations, validations and tests, and are removed at the conclusion of the sequence of operations and/or tests.
One of the first such operations may include loading necessary firmware and software into the drives. The next operations on the drive may include a seeded self-servo write procedure, in which servo information is written to the disk or disks of the drive. During this procedure, servo sector information is written to the drive without using a servo track writer. As servo track writing is a time consuming process that is directly proportional to the areal density of the disk, reducing the number of servo sectors the servo track writer lays down on the disk saves manufacturing time and costs.
Further operations may include a microcode download to the drive, which may be followed by an initial bum in self-test (IBI self-test), in which a lengthy calibration of the drive is performed, as well as procedures to discover, map and manage the defects on the media. The length of time necessary to complete this test is roughly proportional to the storage capacity of the drive under test.
The next and final operations may include administering final configurations and tests. During these operations, the drive communicates with a host computer, so as to verify the proper operation of host commands and to enable the host to analyze and validate the results of the IBI self-test. Other tests and procedures may be carried out on the drives under test, in addition or in place of the tests discussed above, such as a debug process when a fault is found during testing. Such debug tests may be performed to isolate faults, so as to facilitate the correction thereof.
Increasing aerial densities bring about a number of concerns that must be addressed during the administration of these operations and tests. For example, as the number of Tracks per Inch (TPI) of modern drives continues to increase, the drives become increasingly susceptible to vibrations during, for example, the seeded self servo write operations. Such vibrations may originate, for example, from outside of the chassis of the test platform on which these operations are carried out. While the chassis itself may be equipped with structures to mitigate the effects of such vibrations, such structures do not protect the individual drives loaded therein from vibrations that originate from within the chassis. Such vibrations may be generated from adjacent drives within the chassis, as they are subjected to the above-listed operations and tests.
From the foregoing, it may be appreciated that there is a need for vibration reducing structures that mitigate the effects of vibrations that could negatively affect the drive during these operations and test, whether such vibrations originate from within or outside of the chassis in which these operations are carried out.